The present invention relates to novel therapeutic and diagnostic dendrimers. In particular, the present invention is directed to dendrimer-linker conjugates, methods of synthesizing the same, compositions comprising the conjugates, as well as systems and methods utilizing the conjugates (e.g., in diagnostic and / or therapeutic settings (e.g., for the delivery of therapeutics, imaging, and / or targeting agents (e.g., in disease (e.g., cancer) diagnosis and / or therapy, pain therapy, etc.)). Accordingly, dendrimer-linker conjugates of the present invention may further comprise one or more components for targeting, imaging, sensing, and / or providing a therapeutic or diagnostic material and / or monitoring response to therapy.